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Bent Intake Valves w/ Wiseco ProTru Pistons :-(
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Author:  Doctor Dodge [ Wed Mar 03, 2010 9:26 pm ]
Post subject:  Bent Intake Valves w/ Wiseco ProTru Pistons :-(

I talked with Guzzi Mark... (madmax/6)
He installed his new K1 / Wiseco / Jeffrey's head engine, fired it up and bent intake valves. :shock: :evil:

After I successfully talked him down... off the tall building ledge he was threating to jump-off of,
I find-out that the valve notches on the Wiseco pistons, made for the new K1 rods, seem to be "a little off" on placement.
He is collecting more info for us but it looks like I have a call to make to Brian at Wiseco to see if they can cross-check and possibly make an adjustment.

I will say that Mark's combo is pretty wild, using "bigger the normal" oversize valves and a special cam but the valve notches on the Protru pistons are big, they should take the race build's long and high cam/valve events... if the notches are in the right locations.

Well, give Mark an "at-a-boy" for finding this issue... for all of us currently doing builds with these special parts. (I currently have one in process)
DD

Author:  bwhitejr [ Thu Mar 04, 2010 4:45 am ]
Post subject:  Bent Intake Valves

Doc,
There is a drawing in the Slant Six Racing Manual (Fig. 2-4) that lays out the dimensions for notching the pistons. Is this drawing accurate?

bwhitejr

Author:  66aCUDA [ Thu Mar 04, 2010 5:20 am ]
Post subject: 

Dang that suxs. Mark I feel for ya.
Modeling clay is a blessing.
Frank

Author:  Dart270 [ Thu Mar 04, 2010 5:47 am ]
Post subject: 

Good grief that sucks. Mark is a real trooper. Hard to believe they would screw that up. OK, maybe not so hard...

They look like huge notches, so hard to see how they are hitting. I will make sure to check with putty when I assemble mine.

I just did that on my 1.70/1.44 head and by-hand-die-grinder notches - no troubles. I always leave the head gasket out and check for clearance to make sure there is lots. Just hold head down with 2 bolts and turn slowly to feel any interference.

Lou

Author:  Kidd [ Thu Mar 04, 2010 7:16 am ]
Post subject: 

WOW!!! Sorry to hear that.As The first guy to run the weisco/k1 setup, I FEEL YOUR PAIN!!! Keep it up Mark.......if you need to talk, call me.
Andrew

Author:  sergio G [ Thu Mar 04, 2010 7:34 am ]
Post subject: 

Hang in there Marc,feel Your pain,been there with parts breakage over the years. My advise, pull that engine, cover it forget it till after Vegas,then calmly take the thing apart and review the events. Who checked the valve clearance during assembly, was the cam degreed properly..I know this is not the time to look for blame but even if the notches are not big enough for the valves this should be caught during mockup.If i can be of any support please call.

Author:  Doc [ Thu Mar 04, 2010 8:15 am ]
Post subject: 

From the breif discription I got, the "larger then normal" intake valves in this build just cought the edge of the notches... by .030 to .060
A 1.700 valve would have most likely cleared.
Mark is getting me exact measurements so we can figure-out the best way to correct the problem.
DD

Author:  CNC-Dude [ Thu Mar 04, 2010 9:29 am ]
Post subject: 

Having built a large variety of engine types from Chevy, Dodge, Ford and many import brands for racing, as well as used a wide variety of piston manufacturers products, I have rarely seen where the valve reliefs correspond to the actual head you are using, in both location and/or angle. The factory tolerances for the valve locations in most factory production heads is as much as +/-.030 from their centerline, and this can lead to such scenarios as what has happened here if you don't check it thoroughly. I have even seen them be off more than that from cylinder to cylinder in the same head also, especially if guides and seats have been installed or replaced. I had one Super Stock customer that we had to set up and center punch all (8)pistons individually on the intake and exhaust for cutting valve reliefs, because the valve locations can vary that much, that you can't use just one Left or Right piston to reference all of the other pistons to. That is probably what Wiseco is going to say also. There's just too many variables to make a piston with reliefs that will work 100% of the time, even for the same type engine/head combo. Real bummer, I hate to hear about your problem too.

Author:  slantzilla [ Thu Mar 04, 2010 2:13 pm ]
Post subject: 

Did it bend all of them or just 3?

Author:  madmax/6 [ Thu Mar 04, 2010 2:17 pm ]
Post subject: 

I clayed the valve pockets only,The valve hit above the pockets,I should have clayed the entire top of piston.I also had re bushed the dowel pin holes to get the head more centered over my bores,which hurt the position some.Went and picked up 6 new Manley valves today and brought them to a machinest to have them modified for my head.Will dremel the pistons in the car for clearence,hopefully bee running and at the track next thurs.Learning. Mark

Author:  madmax/6 [ Thu Mar 04, 2010 4:10 pm ]
Post subject: 

Valves are 1.760,bent all.My head is also cut 100 thou,so that moves the valve closer up.Mark

Author:  Greg Ondayko [ Thu Mar 04, 2010 7:03 pm ]
Post subject:  Here's What I ran into - Similar combo

I am not sure How much Mike took off my head Yet. the Spec sheet is on it's way..


1.760" Intake Interference Shots for Reference. Pics of Cylinder 6 and 1

I will Be fixing these with A dremel. 1.70's Shoudl be fine but I am not sure about metal expanding at different rates how that will work in an actual running engine.


Greg

Piston #1 Valve Pocket interference - 1.76" intake
Image


Piston #1
Image



Piston #1
Image


Piston #6
Image



Piston #6
Image


Piston # 6
Image

Author:  1969ronnie [ Fri Mar 05, 2010 6:27 am ]
Post subject: 

hi greg, is this the 12-1 you are building and if it is, how far down are the pistons? thanks, ronnie

Author:  sandy in BC [ Fri Mar 05, 2010 10:00 am ]
Post subject: 

Thanks for the incredible pictures Greg.

Author:  Greg Ondayko [ Fri Mar 05, 2010 12:12 pm ]
Post subject: 

Quote:
hi greg, is this the 12-1 you are building and if it is, how far down are the pistons? thanks, ronnie
Yes This is the 12:1 Engine for ruster racer.

The block only has a clean up pass of maybe ~.005"

The pistons are Down .0025" to .008" Most are .005"


No problem on the pics Sandy!


Greg

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